Tuberculosis 2004: challenges and opportunities.

Tuberculosis (TB) continues as a major public health challenge worldwide. HIV-TB coinfection is especially concerning as it accelerates progression of infection to active disease and amplifies spread of TB including drug resistant disease. Application of molecular biology and insights from classic microbiology to TB control have resulted in important innovations in diagnosis and treatment. Radiometric assay and, particularly, PCR, with nucleic acid probing, have reduced the time to diagnosis. Moreover, the sensitivity of these techniques is potentially log orders of magnitude more sensitive. Molecular techniques can be adapted to drug susceptibility testing. The differential activity and post-antibiotic effect of various drugs against TB have led to highly effective briefer regimens and to directly observed therapy. Insights into basic host defense against TB and description of the M. tuberculosis genome have created optimism for developing new treatments and effective vaccines in the years to come.